These prominent "earthworms" are varicose veins of the penis. The venous blood of penis can flow back to the superficial vein outside genitalia through the superficial dorsal vein of penis, and then be injected into the great saphenous vein, and then flow back to the heart with the vein of lower limbs. It can also enter the pelvic cavity through the deep dorsal vein of penis and return to the heart through the internal genital vein. If it is a simple varicose vein of penis, it may be caused by obstruction or obstruction of superficial dorsal vein or deep dorsal vein of penis. There are many reasons for this situation, and suggestions can be made for foreign bodies in veins. If it is a foreign body or stone in the vein, it is difficult to treat it. Only after the diagnosis of penis venography, appropriate surgery is needed. There is no other medication except surgery. If varicose veins appear in scrotum and lower limbs, it is necessary to consider that the veins of lower limbs are also obstructed or blocked, and surgery is also needed.